Dynamo eleoteic machine



(No Model.) 2 Sheets-Sheet 1.

O. M. BALL.

DYNAMO ELECTRIC MACHINE.

N0. 329,118 Patented Oct. 27., 1885.

(No Model.) 2 Sheets-Sheet 2.

O. M. BALL. DYNAMO ELECTRIC MACHINE.

No. 329,118. Patented Oct. 27, 1885.

UNITED STATES PATENT OFFICE) CLINTON M. BALL, OF TROY, NE? YORK, ASSIGNOR TO JOSEPH A. POXVERS, OF SAME PLACE.

DYNAMO-ELECTRICI MACHINE.

SPECIFICATION forming part of Letters Patent No. 329,118, dated October 27, 1885.

Application filed November 24. 1884. Serial No. 148,691.

To all whom, it may concern:

Be it known that I, OLINToN M. BALL, of Troy, in the county of Renssclaer and State of New York, have invented an Improvement in DynamoElectric Machines, of which the following is a specification.

The object of this invention is to maintain a constant electro-motive force with varying resistances in the working-circuit, so that with electric lamps the intensity of the light will not be materially varied by cutting out or bringing in a greater or less number of lamps.

I make use of field-magnets arranged symmetrically, the helices of which are of different resistances and grouped together, the helices of low resistance being in the external or working circuit, and those of high resistance being in a branch or derived closed circuit, both circuits passing through the armature 2o helix or helices, so that the high-resistance helices energize one set or group of field-cores, and the low-resistance helices energize another set or group of field-cores, and these respective field-magnets being arranged sym- 2 5 metrically the eleetro-motive force in the external circuit will remain constant, because if lamps are added in the working-circuit the resistance becomes less, and the volume of electricity flowing through that eireuit,which 0 includes also the coils of a portion of the field-magnets, increases, while that through the circuit of high resistance lessens; but the magnetic energy to set up the current in the armature-helices is not varied materially in 3 5 the gross, because when the greater volume of current is flowing through the circuit of less resistance the magnetic energy of the fieldcores influenced thereby is augmented and the generating capacity of the dynamo is maintained, although the current flowing through the helices of high resistance is lessened; and, on the contrary, when the resistance in the external or working circuit is increased by lessening the number of lamps in multiple are,

an increased but proportionate current flows through the high-resistance circuit, and the energy in the field-cores necessary for the development and maintenance of the required (No model.)

electro-motive force continues in the group of cores under the influence of such high-resist 5c ance circuit. a

In the drawings I have shown myimprovements by diagrams, because my invention is adapted to dynamo-electric machines of various construction, and these diagrams indicate 5 5 the peculiarity in the winding and in the circuit connections. Figure 1 illustrates the improvement with all the helices connected up in series. Fig. 2 illustrates the fine-wi re helices in series and the coarse-wire helices in groups. Fig. 3 illustrates the groups of field helices, and Figs. 4 and 5 the coils of armaturedisks to be used with thefield-magnets in Fig. 3. Fig. 6 is a diagram showing ten helices to illustrate a condition that is objectionable.

In Figs. 1 and 2 the field-helices c b c d of are presumed to be at one side of the revolving armature and facing the helices of the opposite field-magnets, the helix a being opposite to f, at opposite to a, Z) opposite to d, e opposite to I), 850. Let a b c and (2 cf represent the cores and helices of the field-of-force magnets, and h the helix of the armature or the numerous helices of the armature; The helices of a b c and a b c are fine wire, so as to obtain the proper resistance. These arein a circuit the ends of which are united to the respective brushes and of the commutator, and thence to the electrodes of the armature. The helices of cl 6 f d e f are coarse wire, so as to offer but little resistance. These are connected into the circuit 7c Z, in which are are or incandescent lamps m in multiple are, or any other electric working devices. The wire Z connects with the helix f, and the wire k with the brush so that the circuit is completed through the same. The fine wires of the coils a b c a b 0 form a shunt or derived circuit'to the working-circuit passing through d e f and the lamps or external devices.

When but one lamp m is in operation, the resistance in the working-circuit will be great, and the current developed will go principally through the fine wire and helices of the shunt or derived circuit. The magnetism in cores of (1 cf will be very feeble, but in a b c it will be strong enough for the setting up of the proper current in the armature-helices. If, now, numerous lamps in are turned on, the resistance in the working-circuit will be lessened, and more current will pass over the working-circuit and less will pass through the shunt-circuit; hence the magnetism in (Z c f will be augmented in the same proportion as the magnetism in a b c is weakened. The object of this feature is to provide a means of maintaining a constant electro-inotive force at the translating device. This is accomplished by the use of series coils, which shall increase the magnetism of the field-magnets as the resistance of the external circuit is lessened, by which lessening the resistances of armature and line become an appreciable part of the total resistance of the circuit,so much that the armature shall produce an increase of electromotive force sufficient to force the quantity of current required by the translating devices in circuit through the armature and line without lessening the electromotive force at the translating devices, so that but little variation inv the light of any given lamp will OC0l1I,\Vll6i}lJ6I' there are numerous lamps or but few in the circuit.

It is to be borne in mind that if the workingcircuit is broken magnetism in def will cease; but the magnetism in a b 0 will be increased to its maximum, and the dynamo, having an initial magnetic field, will remain in a working condition, ready to send a current upon the main or working circuit as soon as it is closed. On the other hand, there is a limit to the ca pacity of the machine, and care should be taken not to reduce the resistance in the workingcircuit so low as to divert all the current from the shunt-circuit.

In Fig. 1 I have shown the helices upon the magnet-cores connected up in two series, the helices a b c and wires 1 2 3 4 being in a branch or derived circuit, and the helices d ef in series in the main or working circuit. The helices a b c are of fine wire, and d e f of coarse wire.

In Fig. 2 the same helices, cores, and armature-coils are shown, and the shunt-helices a b c a b c are in series, as before, but the respective ends of the helices d e f d e f are grouped together at 7 and 8, this connection being designed to further reduce the internal resistance in d e f cl 6 f, according to the wellknown principles. The circuit-wire Z in this case is connected at 8 and the commutatorbrush at 7.

It is now to beunderstood that in dynamoelectric machines in which one circular range of field-magnets is employed the coarse and fine helices should alternate all around the circular range, there being an even number of field-helices, so that each group of elements will be symmetrical with the other.

If the dynamoelectric machine has two circular ranges of field-magnets, with the cores N S alternating and opposing each other, and the armature-wheel revolving between the poles, the fine-wire helices may under some circumstances all be in one of the circular ranges,and the coarse-wire helices maybe all in the other circular range upon opposite sides of the armature-wheel, or the coarse and fine helices may alternate in each circular range, as indicated in Figs. 1 and 2. In either case the symmetry of the field-magnets will be maintained, because the cores will be always magnetized of the proper polarity; but the magnetic energy will rise and fall according to the electric energy in the line or coarse helices. As the direction of current is not reversed in the field-helices,the polarity of the cores will not be altered by the rise and fall of the strength of the current.

For the purpose of illustration I have shown in the diagrams, Figs. 8, 4, and 5, my present invention as applied with a diilerent number of armature-coils from the number of fieldhelices, as in my Patent No. 290,199, granted December 18, 1883.

I have represented in Fig. 3 field-magnets containing eight elements. TheNand S poles are to be opposite to each other, and between them is presumed to revolve the armaturecoils, Fig.4, or those of Fig. 5, as in said patent. The coils of the armature are to be connected in a closed circuit with branch wires to the commutatonplates, as more fully set forth in said patent. In Fig. 4 there are shown ten armature-coils, and in Fig. 5 there are shown siX armaturecoils. Vhen either of these armatures is caused to revolve between the two circular ranges of field-magnets having eight elements, as in Fig. 4, the currents will flow toward the commutator-brush and return by the commutatonbrush -,upon the principles laid down in said patent.

The proper operation of machines constructed according to this plan depends upon the absolute symmetry of the magnetic field upon the two sides of a diametric line passing through the armature and field, as represented by the lines as.

To apply my present improvement to this machine the coarse and fine wire helices may alternate at the poles-say fine wire on (6 ob r a b cr, coarse wire on f c d s f e d s. This arrangement will be operative because the fields on both sides of w 00 are equal in number and kind, therefore symmetrical, and are in harmony with the armature, so as to properly induce the currentstherein. Inlike manner,if the helices a f 0 e b d r s were all wound with fine wire and a f 0 e Z) d r s with coarse wire, the symmetry and efficiency will be maintained. If, however, the field should be composed of a number of which one-half was an odd number--such, for instance, as ten poles in the field-and an armature of either eight or twelve elements were used with the same, and the fieldpoles throughout each circular range were wound alternately with coarse and fine wire, the arrangement would be obj cctionable. This is illustrated in Fig. 6, from which it will be current coinciding in point of time with the seen that if a, 0, b, r, and t are fine wire and f e d s a are of coarse wire,the field will be unsymmetrical on account of there being three 5 fine-wire poles, b r t, on one sideof the diameter 00 00, and only two, a 0, on the other, the same being true also of the coarse-wire poles, but in reverse condition. This arrangement of helices is to be avoided. If, however, there are ten poles in the field at each side of the revolving armature and eight or twelve armature elements, and all the poles on one side of the armature are wound with fine wire, and all the poles on the other or opposite side are wound with coarse wire, the arrangement will be efi'ective, as before described.

The connections of the circuit are to be maintained in the order hereinbefore set forth-that is to say, the fine-wire helices are in a branch or derived circuit, and the coarsewire helices are in the external or working circuit, and both circuits pass through the armature.

Again, in my Patent No. 294,719 I have shown another arrangement of field and armature elements, and a system of commutation of the currents developed in a double range of armature-helices, wherein the currents are collected and taken up from the two armature systems intermediately, the maximum of one minimum of the other.

By reference to that patent it will be seen that an absolute equality of the magnetic field upon the two sides of the armature wheel or 3 5 disk is necessary. Hence the properarrangement when the present improvement is applied in machines of that character is to make the alternate poles, respectively, as in Figs. 1 and 2, of coarse and fine wire, and not fine wirefall 40 upon one side of the armature and coarse wire upon the opposite side.

I claim as my invention The combination, with the revolving-armature coils and commutatonconnections, of two circular ranges of field magnets, between which the armature revolves, and helicesifor the field-magnets of coarse and fine wire arranged alternately, and branch circuit connections for the fine-wire helices, and conneco tions between the coarse-wire helices and ,the external or working circuit, substantially as set forth.

Signed by me this 13th dayjof November,

CLINTON M. BALL.

W'itnesses:

Ormnrns H. TOLHURST, G. 0. S. CONWAY. 

